Using Flashback to return Past States

-- Based on: "Oracle Flash Back Query Explained with Example", oracle-dba-online.com – https://www.oracle-dba-online.com/flash_back_features.htm

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-- Using Flashback Table to return Table to Past States.
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-- Row movement must be enabled on the table for which you are issuing the FLASHBACK TABLE statement. 
-- You can enable row movement with the following SQL statement:

ALTER TABLE emp ENABLE ROW MOVEMENT;

-- The following example performs a FLASHBACK TABLE operation the table emp

FLASHBACK TABLE emp TO TIMESTAMP TO_TIMESTAMP('2007-06-19 09:30:00', 'YYYY-MM-DD HH24:MI:SS');

/*
Example:-
At 17:00 an HR administrator discovers that an employee "JOHN" is missing from the EMPLOYEE table. 
This employee was present at 14:00, the last time she ran a report. 
Someone accidentally deleted the record for "JOHN" between 14:00 and the present time. 
She uses Flashback Table to return the table to its state at 14:00, as shown in this example:
*/

FLASHBACK TABLE EMPLOYEES TO TIMESTAMP
      TO_TIMESTAMP('2007-06-21 14:00:00','YYYY-MM-DD HH:MI:SS')
      ENABLE TRIGGERS;

-- IMPORTENT
-- You have to give ENABLE TRIGGERS option otherwise, by default all database triggers on the table will be disabled.